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Topic: Gray smoke spit from carbs (Read 3569 times)

Double check your pushrod adjustments, to be sure that they are not too tight.Adjust them when the engine is cold, and have no perceptible up/down play, but NEVER too tight. They should easily spin with finger spinning when cold.

The mechanics in India are notorious for setting pushrod adjustment too tight, in an effort to make the bike quieter. This is VERY bad and should NEVER be done.

Too-tight adjustment of the pushrods can cause this kind of spitting back, in some cases. I'm not saying it IS causing it in your engine, but it should be checked, especially if any Indian mechanic had his hands on it.

Engine was assembled here in India by one of those "mechanics," but when I spoke to him about the engine we even discussed how the timing marks were supposed to be oriented. Haven't opened the timing cover myself to check it out, but since there's no other performance-based additions to the engine I would doubt that's the problem.

I retarded the timing a hair. I am still, it seems, unable to clearly differentiate ping from the normal valve noise. Someone else described it as something like the sound of a ball-point pen clicking rapidly, but I'm also thinking that's what my valves sound like at high RPM.

What I suspected was ping sounded like a small rattlesnake somewhere on my rockerbox. Not clearly audible unless you were paying particular attention to the engine sound, and although it seemed to stop when you let off throttle, it was very rhythmic. Is this just the sound of my valves?

Engine was assembled here in India by one of those "mechanics," but when I spoke to him about the engine we even discussed how the timing marks were supposed to be oriented. Haven't opened the timing cover myself to check it out, but since there's no other performance-based additions to the engine I would doubt that's the problem.

I retarded the timing a hair. I am still, it seems, unable to clearly differentiate ping from the normal valve noise. Someone else described it as something like the sound of a ball-point pen clicking rapidly, but I'm also thinking that's what my valves sound like at high RPM.

What I suspected was ping sounded like a small rattlesnake somewhere on my rockerbox. Not clearly audible unless you were paying particular attention to the engine sound, and although it seemed to stop when you let off throttle, it was very rhythmic. Is this just the sound of my valves?

Regarding the ping noise, you can differentiate it by when it happens.The valve/tappet noise is always there.The ping noise is only there under loads with the throttle open further than normal, such as on hills at rpms below 3500, or exceptionally hard acceleration, or lugging the engine.

The ping will go away if you back off the throttle when you are hearing it.The valve noise will not go away.

The disappearance when I've backed off throttle is what's made me consider it ping; I just started to think maybe it was just how the valves sounded at a certain RPM. It's kind of hard to separate all the sounds.

What I could use is a relative idea of how loud the noise is...the sound I hear you really need to listen for, whereas when someone says "ping" I imagine a noise that would make me say "What the HELL was that??"

Ping does not have any harmonious timing with the engine noises.The ping is just randomly occurring metallic clicking noises that do not coincide at all with any engine noises or rpm speed.It's like as if your keys were rattling and jiggling against the handlebars or something, only under hard load conditions. That kind of noise.

I feel silly asking, but can anyone comment on the volume of pinging, rather than how it sounds? Is it clearly audible as you're riding along, or do you generally need to be paying attention to hear it?

I kinda like some pea gravel in a coffee can rattle analogy but with a single cylinder it's more like one pea gravel in the can and it often happens at about the same frequency as the thumps of the exhaust.